The detection and quantitation of chemical substances including immunological substances represents an ongoing problem for many diverse disciplines. In the environmental area, for instance, the detection of dangerous compounds in air, water, and earth often requires extensive chemical tests and analyses. Certain carcinogens are excluded by fiat at any level in drinking waters, yet their detection even at relatively high levels is often impossible because of a lack of sensitivity of conventional testing. As more substances are recognized to be dangerous to the health of humans, new tests and analytical techniques will be required.
In the context of the present invention, the detection and quantitation of relatively small amounts of specific immunological substances such as immunoglobulin IgE is especially important for the diagnosis and for the treatment of allergenic reaction of certain individuals. Generally, such substances are present at extremely low levels in human serum. Accordingly, the detection and quantitation of certain types of IgE and their association with particular allergens can be well correlated with specific allergies experienced by the serum donor.
A further area wherein the detection and quantitation of a particular chemical substance is desirable, if not mandatory, is the field of virology. Viruses are generally believed to be complex molecules of DNA surrounded by a protein sheath and, as such, are said to represent the very smallest of life forms. They are thought to be the causitive agents of many diseases such as hepatitis, herpes, mumps, polyomyolitis, among others, and have already been identified with various types of cancer. The importance of detecting such viruses, at an early stage, of course, cannot be overstated.
Thus, the detection of the aforementioned chemical substances and other similar substances has represented a critical but most difficult, and, in some cases impossible task.
Extensive analytical, spectroscopic, radioisotopic, and biological test procedures have been developed in an attempt to fulfill these detection requirements. However, many conventional procedures are relatively insensitive yet rapid, while other procedures are extremely sensitive,yet relatively slow.
Typically, the specific chemical substances sought to be detected have been determined by one or two best specialized techniques or procedures. Despite the plethera of methods, no one methodology represents an ideal solution for the multitude of specific substances and no one method lends itself to universal application. Radioimmunoassay techniques, however, do have very broad ranges of applicability for chemical substances of biological origin.
New approaches for such detection and quantitation are constantly sought and with each, a commensurate new range of detection possibilities thereby results.
Among these approaches are the multitude of specific assays utilizing optical analyzers, for instance, those disclosed in the following U.S. Patents issued to Philip J. Wyatt as sole or joint inventor: U.S. Pat. No. 3,624,835--Microparticle Analyzer Employing a Spherical Detector Array, (Nov. 30, 1971); U.S. Pat. No. 3,730,842--Process for Determining Bacterial Drug Sensitivity with R. M. Berkman and D. T. Phillips (May 1, 1973); U.S. Pat. No. 3,754,830--Scattering Cell Employing Electrostatic Means for Supporting a Particle with D. T. Phillips, H. H. Brooks and C. R. Liu (Aug. 28, 1973); U.S. Pat. No. 3,770,351--Optical Analyzer for Microparticles (Nov. 6, 1973); U.S. Pat. No. 3,815,000--Levitator with D. T. Phillips, H. H. Brooks and C. R. Liu (June 4, 1974); U.S. Pat. No. 3,928,140--Apparatus and Process for Testing Microparticle Response to its Environment with V. R. Stull, W. L. Proctor and I. L. Miller (Dec. 25, 1975); and U.S. Pat. No. 4,101,383--Apparatus and Process for Testing Microparticle Response to its Environment --with V. R. Stull , W. L. Proctor and I. L. Miller (July 18, 1978).
Such disclosures are hereby specifically incorporated by this reference.
Accordingly, those skilled in the art have recognized a significant need for a sensitive yet relatively rapid detection and quantitation technique which lends itself to a broad range of applications. The present invention fulfills these needs.